The present invention relates generally to agricultural bale handling and hauling machines, and more particularly to such a control system for a bale wagon that automates the loading of large bales onto a bale wagon.
A large proportion of the resources and time of the agricultural industry is directed toward the production of feed for animals, and most specifically to the production of baled stem and leaf crops such as hay. The conventional process is to cut and condition the crop with a windrower, deposit it on the ground to dry, bale the crop when appropriately dry, and then position the bales in stacks for storage or transportation. High labor requirements and increasing costs of manual handling of bales have caused a growing number of commercial growers to abandon their small square bale operation for a large bale package, such as round bales, or large rectangular bales 3′×3′, 3′×4′, or 4′×4′ in cross-section. Due to the large size of the bales, there is a need for equipment which can pick up the bales in the field, accumulate a load of bales, and transport them to a remote storage area where the accumulated bales can be unloaded. Also, such equipment must be flexible in the ability to deal with bales of varying sizes. Furthermore, it is important that the bale handling equipment be able to arrange and control the position of bales on the transporter bed after the bales have been picked up.
Commercial haulers prefer large square bales over small square bales because they can be retrieved from a field and loaded for a cross-country trip in less than an hour. Large rectangular bales are loaded onto flat-bed trucks or semi-trailers directly in the field at about 20 tons per man-hour. Transporting larger loads of bales reduces fuel usage and the time required for bale handling. It is these large rectangular bales that have become increasingly popular over the last several years, and to which this invention is most concerned.
The Mil-Stak® big bale loading attachment was developed as a way incorporate big bale handling capability on self-propelled or pull-behind bale wagons. The Mil-Stak® big bale loading attachment comprises a bale clamping apparatus connected to a pivoting lifting arm. The lifting arm is coupled at one end to the bale wagon for pivotal motion about a single axis, the axis being angled relative to the bale wagon. Loader arm movement is accomplished by a single actuator acting on a lever arm to pivot the lifting arm through approximately 180 degrees of motion. A second actuator actuates the clamping apparatus. The actuators are manually controlled by an operator from the cab of the bale wagon from where he can observe the bale position and manage actuator motions accordingly.
The Mil-Stak® bale loading attachment was developed as a retrofit solution for a bale wagon enabling big bales to be efficiently gathered from the field and loaded onto the bale wagon. The Mil-Stak® loading attachment replaces the bale loading normally supplied with a bale wagon and allows big bales to be loaded onto the bale wagon. The replacement also renders certain bale handling operations necessary for small bale loading unnecessary, so the bale wagon must be operated in a manual mode when using the Mil-Stak® attachment. The Mil-Stak® attachment requires and offers minimal controls accessible to the operator through a small electromechanical operator interface requiring manual operator input for all loader movements. Manual control introduces difficulty in that the single hydraulic actuator used to reposition the bale loader arm requires reversing the direction of the actuator as the loader arm reaches an apogee in the pivotal motion. The operator must, therefore, precisely actuate a switch which causes the actuator to reverse its direction of movement at the loader arm apogee, allowing momentum to move the loader arm through the apogee position smoothly. The inertial effect of a bale in the clamping apparatus assists the operator through the transition during the loading sequence; however, returning the loading arm to retrieve the next bale requires moving through the apogee position without the inertial assist of a bale.
In addition to managing operating of the bale loading actions, the operator must also operating the bale wagon itself, guiding it around the field to position bales on the ground within reach of the bale clamping apparatus and controlling movement of the bale tilting table that creates the stack of bales on the load floor. The result is that significant operational demands are placed on the bale wagon operator which lead to increased fatigue and ultimately affect productivity. It would be advantageous to provide a control system to automate portions of the Mil-Stak® bale loading cycle. Further advantages would be realized with a control system that operably coupled several portions of the loading cycle and provided a complete control system capable of automating the entire bale loading sequence up to and including preparation for bale load transport.